Burglar alarm



Dec. 2o, 1927.

J. P. MARTINKA BURGLAR ALARM Filed Sept. 25.. 1926 Patented Dec. 20, 1927.

UNITED STATES PATENT oFFICE.

JOHN P. MARTINKA, or EL CAMPO, TEXAS.

BURGLAR ALARM.

Application filed September 25, 1926. Serial No. 137,659.

This invention relates to certain 4new andk useful improvements in burglar. alarms, andv has more particular reterence tek burglar spring motor operated bell, and means ren-l dered operable upon closing of a door and retention oi' the door in closed position, for preventing operation of the bell motor and soundingk of thebell, and for releasing Ythe bellinotor upon subsequent opening ofthe door by lan unauthorized lperson` so fas to d cause sounding of' the bell.

Almere speciiic object 1s to provide an` alarm of the 'above kind embodying a. spring motor operated bell land means operableupen closing of 4a door for `ivindingthe motor of the hellend.maintaining the motor Wound and inoperative as long as the door is retained closed, said means being releasable upon subsequent opening ot the door for per* initting operation of the bell motor and` n motor spring, yby means of a gearing includf ing a relatively large segment geal416 iXed y `upon thewinding shaft 15. T

sounding of the bell. l d

Other objects `will become apparentl as the nature of the invention is better understood,

and the same consists inthe n ovel form,

combination and arrangement Of parts'heref in'atter more `fully described, shown in the.

accompanying drawing and claimed.

In the drawing, Whereinlike reference` characters indicate corresponding vparts throughout thevseveral views,

Figure 1 is' an elevational view of anL alarm device constructedin accordance with the present inventionand operatively associated with a swingingdoor,

Figure 2 is a vievv thereof partly in top plan and partly. in section ony line Z-Zof' Figure 1;

Figure V3 is an enlarged elevational View of the springmotor operated bellforining a part oft thealarmdevice shown inA Figures l and2;and

Figure 4 is an enlarged detail View .partly in `horizontal section, shoiviiig thek door and the adjacent parte of the controlled thereby. l y

Referring moreA 'n detail to .thedrawing,y `they ypresent invention embodies a spring alarm operatedjand `ect ot the present inveny motor operatedy bell including a suitable frame preferably composedot a relatively large plate 5 havingv a pair of spaced sound producing shells@ mounted upon the inner side of the upper portion thereof, and a sec- 0nd .smaller plate 7 suitably` rigidly con-` nected to but sp'aeedfrom. and parallel with thelower portion of the plate 5. 1 Supported by and inountedbetween the plates .5 and 7 is a conventional spring Voperated motor ineluding-a spring rotated drive .shaft 8 and an escapement Wheel y9 geared to and driven thereby in a manner W All known inthe art. This motor further includes a swinging. 'or oscillatory4 escapement lever 10 operatively having its upper end connected by a link 11 With the intermediate portion of an oscillatory hammer 12 which is pivotally mounted at its lower end as at 13 andprovided withl 'y The spring motor further?. embodies a- Winding shatt 15 Which is operatively connected to the drive shaft 8 for Winding the A lever isprovided for actuating or turning the segmentgear 16 to cause windingof the motor spring, and, this lever includes an inner section or ,armv 17 rigid with thegear 16` atv a point intermediate the ends lof the` curved toothed edge of the same and depend` ing as shown :in Figure 3. f VThe operating associated with ythe escapeinent wheel 9 and i Si t) lever otfgear, 16 further includesl an outer orf` lower section tor arm 18 oi yU-shape cross sec tion, the upper end portion. of which embraces, the upper or inner arm 1T and is pivoted to the lower end of the latter as at 19. It is thus apparent `thatztlieouter section 18 ot the lever may be swung to various angular positions relative` tothe innery arm 17, and

in 'order to maintain the arm 1,8 of the lever y in any of such angularly. adjusted positions,v

said -arm 18, is provided with yan arcuate series of transverse opening 2O adapted for kselective reception of the laterally directed free yends lotfa.spring arm 21 having `one end suitably Iixed, to thesegment gear 16. With the laterally directed end of the spring arm 21inserted throughwone' ofthe apertures20A viio and across the adjacent edge of ythe arm 17 as shown in Figure 3, the arm 18 will be prevented from swinging to the left of Figure 8 relative to arm 17. In a like manner, if the spring arm 21 is disengaged and the lever arm 18 is swung to the right of Figure 8 until the uppermost opening 21 passes the left hand edge of arm 17, saidspring arm 21 may be inserted in said uppermost opening 2O so as to contact the adjacent edge of arm 17 and maintain the arm 18 in such adjusted position relative to the arm 17. The purpose of this construction will presently becomeA apparent.

Referring to Figures 1, 2 and t, 22 indicates a door trame upon which is 'hung a conventional horizontally swinging and outwardly opening door 23. Slidably disposed and guided for limited movement through the vertical stop strip 24 of the door frame 22 engaged by the free vertical edge portion of the door when closed, is a horizontal rod or plunger 25 whose inner end is arranged to engage the free end oi one arm of a horizontally swinging bell crank lever 26 suitably mounted on the inside of the door frame 22 so that when the plunger 25 is forced inwardly said bell crank lever 26 is caused to exert a pull upon a pull rod 27 having one end connected to the free end of the other arm of said bell crank lever as shown. The other end of pull rod 27 is pivotally connected to the free end of the arm 18 of the actuating lever for segment gear 16.

The plates 5 and 7 of the bell frame are provided with lateral flanges 28 so as to facilitate rigid mounting otl the bell upon a wall within the dwelling equipped with the door 23, as indicated in Figs. 1 and 2.

For an understanding of the operation of the device, it is to be understood that the lever composed of arms 17 and 18 is adapted vto be swung to the left of Figures 1 to 3 inclusive for elieeting winding of the motor spring. It is also to be understood that when the spring of the motor unwinds for actuating the hammer 12, the segment gear 16 will alsojbe turned so as to cause return swinging movement of the lever composed oi' arms 17 and 18, to the right of said figures. Thus, with the device installed ask shown in Figures 1, 2 and 11, it will be seen that when the door 23 is closed it will en-` gage the rod or plunger 25 and `force the same inwardly so as to cause swinging o'lf the bell crank lever 2G and thereby exert a pull rod 25 will be released so as to allow movement of the rod 27 as'caused by turning of' the segment gear 16 under the influence o the spring motor. Thus, with the alarm set and the door thus surreptitiously opened, an alarm will be sounded for warning the occupants of the dwelling. Naturally, `the sounding of the alarm will only continue until the motor spring unwinds to return the parts to normal position with the plunger or rod 25 projected. It will also bev apparent that by angularly adjusting the lever arm or section 18 relative to the section or arm 17, the distance oi projection or the. plunger or rod 25 upon full unwinding of the motor spring may be varied so that the winding movement of segment gear 16 is accordingly varied and the subsequent length of time which the alarm is sounded may be accordingly changed. In some instances, it may be desirable to have the alarm sound as long as possible in order that the alarm may be sure to be heeded. In other cases, however, it may be desirable' to onlyhave the alarm sound tor a comparatively short interval,

such as when the user is sure of being in the vicinity of the alarm and does not desire any possibility of the burglar hearing the same when sounded. It will thus be apparent that the adjustment of the arm sections 17 and 18 relatively, is of importance.

From the foregoing description it is believed that the construction and operation as well as the advantages of the present invention will be readily understood and appreciated by those skilled in the art.

Minor changes may be made without departing from the spirit and scope of the invention as claimed.

lVhat I claim as new is 1. A burglar alarmcomprising in combination, a spring motor, a bell operated thereby, said motor including a'winding shaft', an operating lever for said shaft, a pull rod connected at one end to said lever, a bell crank lever having one end connected to the yother end of said pull rod, and a plunger projectable upon closing of a door by engagement of the door therewith ior causing swinging of the bell crank lever and exerting a pull upon vthe pull rod for winding the spring motor of the bell, said plunger" being releasable upon opening movement of the door for permitting unwinding of the motor and sounding of the bell. Y

2.. In a burglar alarm, the combination with a door frame having a stop strip, and a door mounted in the frame and 'engageablev with said stop strip when closed, a plunger slidably mounted through said stop strip so `as to beengageable and project-` able by the door when closed, a springmotor operated bell, and an operative'connection between the plunger andthe motor of the bell for causing winding of said motor lill) upon closing of the door, said plunger being releasable upon opening movement of the door for permitting unwinding of the motor and sounding of the bell.

8. In a burglar alarm, the combination with a door frame having a stop strip, and a door mounted in the frame and engageahle with said stop strip when closed, a plunger slidably mounted through said stop strip so as to be engageable and projectable by the door when closed, a spring motor operated bell, and an operative connection between the plunger and the motor of the bell for causing Winding of said motor upon closing of the door, said last named means embodying a lever vfor operating the Winding shaft of the bell motor composed ol' a pair of arms, one angularly adjustable relative to the other, for varying the distance of projection of the plunger, ysaid plunger being releasable upon opening movement of the door for permitting unwinding of the motor and sounding of the bell.

Iu testimony whereof I alix my signature.

JOHN I). MARTINKA. 

